PISTON FOR HIGH-PRESSURE PISTON IN CYLINDER PART, HAVING GROOVE AND WEAR-PREVENTING PROTECTIVE LAYER IN SURFACE AREA OF PISTON

摘要

PURPOSE: A piston for a high-pressure piston in a cylinder part is provided to reduce wear of a control or injection valve and to lengthen the life span of the valve in injecting water. CONSTITUTION: In a piston(20) for a high-pressure piston in a cylinder part(15) of a control or injection valve injecting water, a groove(22) and a wear-preventing protective layer are formed to the surface area of the piston. The high-pressure piston in the cylinder part includes the piston and a cylinder bore(19). The piston is movably arranged in the cylinder bore. The surface area of the piston and/or the cylinder bore has the wear-preventing protective layer.